In the past thirty years, I've run thirty-three full marathons. I've run marathons all over the world, but whenever someone asks me which is my favorite, I never hesitate to answer: the Boston Marathon, which I have run six times. What's so wonderful about the Boston Marathon? It's simple: it's the oldest race of its kind; the course is beautiful; and--here's the most important point--everything about the race is natural, free. The Boston Marathon is not a top-down but a bottom-up kind of event; it was steadily, thoughtfully crafted by the citizens of Boston themselves, over a considerable period of time. Every time I run the race, the feelings of the people who created it over the years are on display for all to appreciate, and I'm enveloped in a warm glow, a sense of being back in a place I missed. It's magical. Other marathons are amazing, too--the New York City Marathon, the Honolulu Marathon, the Athens Marathon. Boston, however (my apologies to the organizers of those other races), is unique.

What's great about marathons in general is the lack of competitiveness. For world-class runners, they can be an occasion of fierce rivalry, sure. But for a runner like me (and I imagine this is true for the vast majority of runners), an ordinary runner whose times are nothing special, a marathon is never a competition. You enter the race to enjoy the experience of running twenty-six miles, and you do enjoy it, as you go along. Then it starts to get a little painful, then it becomes seriously painful, and in the end it's that pain that you start to enjoy. And part of the enjoyment is in sharing this tangled process with the runners around you. Try running twenty-six miles alone and you'll have three, four, or five hours of sheer torture. I've done it before, and I hope never to repeat the experience. But running the same distance alongside other runners makes it feel less grueling. It's tough physically, of course--how could it not be?--but there's a feeling of solidarity and unity that carries you all the way to the finish line. If a marathon is a battle, it's one you wage against yourself.

Running the Boston Marathon, when you turn the corner at Hereford Street onto Boylston, and see, at the end of that straight, broad road, the banner at Copley Square, the excitement and relief you experience are indescribable. You have made it on your own, but at the same time it was those around you who kept you going. The unpaid volunteers who took the day off to help out, the people lining the road to cheer you on, the runners in front of you, the runners behind. Without their encouragement and support, you might not have finished the race. As you take the final sprint down Boylston, all kinds of emotions rise up in your heart. You grimace with the strain, but you smile as well.

* * *

I lived for three years on the outskirts of Boston. I was a visiting scholar at Tufts for two years, and then, after a short break, I was at Harvard for a year. During that time, I jogged along the banks of the Charles River every morning. I understand how important the Boston Marathon is to the people of Boston, what a source of pride it is to the city and its citizens. Many of my friends regularly run the race and serve as volunteers. So, even from far away, I can imagine how devastated and discouraged the people of Boston feel about the tragedy of this year's race. Many people were physically injured at the site of the explosions, but even more must have been wounded in other ways. Something that should have been pure has been sullied, and I, too--as a citizen of the world, who calls himself a runner--have been wounded.

This combination of sadness, disappointment, anger, and despair is not easy to dissipate. I understood this when I was researching my book "Underground," about the 1995 gas attack on the Tokyo subway, and interviewing survivors of the attack and family members of those who died. You can overcome the hurt enough to live a "normal" life. But, internally, you're still bleeding. Some of the pain goes away over time, but the passage of time also gives rise to new types of pain. You have to sort it all out, organize it, understand it, and accept it. You have to build a new life on top of the pain.

* * *

Surely the best-known section of the Boston Marathon is Heartbreak Hill, one in a series of slopes that lasts for four miles near the end of the race. It's on Heartbreak Hill that runners ostensibly feel the most exhausted. In the hundred-and-seventeen-year history of the race, all sorts of legends have grown up around this hill. But, when you actually run it, you realize that it's not as harsh and unforgiving as people have made it out to be. Most runners make it up Heartbreak Hill more easily than they expected to. "Hey," they tell themselves, "that wasn't so bad after all." Mentally prepare yourself for the long slope that is waiting for you near the end, save up enough energy to tackle it, and somehow you're able to get past it.

The real pain begins only after you've conquered Heartbreak Hill, run downhill, and arrived at the flat part of the course, in the city streets. You're through the worst, and you can head straight for the finish line--and suddenly your body starts to scream. Your muscles cramp, and your legs feel like lead. At least that's what I've experienced every time I've run the Boston Marathon.

Emotional scars may be similar. In a sense, the real pain begins only after some time has passed, after you've overcome the initial shock and things have begun to settle. Only once you've climbed the steep slope and emerged onto level ground do you begin to feel how much you've been hurting up till then. The bombing in Boston may very well have left this kind of long-term mental anguish behind.

Why? I can't help asking. Why did a happy, peaceful occasion like the marathon have to be trampled on in such an awful, bloody way? Although the perpetrators have been identified, the answer to that question is still unclear. But their hatred and depravity have mangled our hearts and our minds. Even if we were to get an answer, it likely wouldn't help.

To overcome this kind of trauma takes time, time during which we need to look ahead positively. Hiding the wounds, or searching for a dramatic cure, won't lead to any real solution. Seeking revenge won't bring relief, either. We need to remember the wounds, never turn our gaze away from the pain, and--honestly, conscientiously, quietly--accumulate our own histories. It may take time, but time is our ally.

For me, it's through running, running every single day, that I grieve for those whose lives were lost and for those who were injured on Boylston Street. This is the only personal message I can send them. I know it's not much, but I hope that my voice gets through. I hope, too, that the Boston Marathon will recover from its wounds, and that those twenty-six miles will again seem beautiful, natural, free.